William r



w. H. CLARK. GAS OPE,

APPLICATION FILED MAY v24, 191].

RATED GUN.

Patented June 24, 1919.

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llllllllf /NvEN'ToR m l ATTURNEY" UUUIUII I\AUUIII UM! Ullull W. R. CLARK. GAS OPERAT'ED GUN. APPLICATIQN FILED MAY 2.4. l9ll.

Patented J1111e'24, 1919.

N MNR WILLIAM R. CLARK, OF SEATTLE, WASHINGTON, ASSIGNOR 0F ONE-HALF TO WILLIAM MARTIN, OF SEATTLE, WASHINGTON.

GAS-OPERATED GUN.

Specification of Letters Patent.

Patented June 24, i919.

' Application filed May 24, 1917. Serial No. 170,622.

tion to improve the construction of guns of this character to render the same more simple and eilicient in operation.

The invention consists in the various operating mechanisms which are selectively actuated either manually or by the energy afforded by the pressure of gases generated in firing the gun.

It further consists in devices for regulating the effective pressure of such gases so as to vary fthe speed of the gun mechanisms in continuous firing. It further consists in the provisionof improved breechlocking and releasing appliances. It further consists in meanszto prevent. the gun barrel from becoming unduly heated from rapid discharges.

rIhe invention further consists in the novel construction, adaptation and combination of Vparts as will be hereinafter described and claimed.

In the accompanying drawings- Figure 1 is a view in side elevation of a gun embodying features of my invention. Fig. 2 is a detail view in vertical longitudi nal section through the receiver and a portion of the stocl and barrel of the gun, the parts of the mechanisms being shown in pol sitions which they occupy when the gun is discharged. Fig. 3is a similar view showing the parts inthe positions which they occupy when` the breech-'bolt is retracted and a charged shell has been raised into loading position.' Fig. 4 is a view in vertical longitudinal section of the forward portions of the gun. Fig. 5 is a fragmentary view similar to Fig. 4v Ito illustrate the plunger in a different operative position from which it is therein shown. Fig. 6 is a transverse sectional View through 6-6 of Fig. 4. Figs. 7 8 and 9 are transverse sectional views through 7-7, 8-8 and 9 9 of Fig. 2.' Figs. 10, 11 and-12 are sectional views taken substantially through 10-10, 11-11 and 12-12 of Fig. 3. Fig. 13 is Vprovided in the receiver.

a fragmentary side elevational view of one of the operating bars and a sector gear con.

nected therewith.

In said drawings, the reference letter A designates the barrel, B the frame or receiver, and C the stock of a gun. The reduced rear end of the barrel is threaded,

as at 1, andengages in a correspondingly threadedopening .in the receiver, being further secured' by a lock-nut 2 engaging threads 3 of the barrel and screwed firmly against the end of the" receiver.

Fitted upon said'barrel and in spacedrelation to the receiver is a sleeve 4, said sleeve being secured between a disk-shaped nut 5 at the rear engaging the barrel threads 3, and a muzzle cap 6 engaging screw threads 7 provided on the forward end of the barrel. Said sleeve is constructed of a material having a relatively high conductivity for heat, and is desirably provided in itsv outer periphery with a number of grooves 8 to furnish a large heat-radiating surface.

The sleeve, furthermore, is provided with a plurality of longitudinal air-cooling passages 9 which communicate from the rear with the external atmosphere Ithrough holes 10 provided in lthe nut 5 and at the front through communicating passages 11 and a chamber 12 provided in the cap 6.

The passagesY 11 are directed toward the axis. of the gun 'barrel at a short distance in advance of the muzzle thereof so that suction will thereby lbe developed by the passage of a projectile to cause air for cooling purposes to flow in the direction of the latters travel through the various passages 9.

threaded at one end into the cylinder, said tube having screwed into its other end an apertured plug 151 and lits into a socket This cylinder is communicatively connected with the gun bore by a duct 16 extending through a nipple 17. Fitted into the cylinder bore is a piston 18 having a screw-threaded stem 19 ,which extends through a threaded aperture in a closure 20 detachably connected to the forward end of the cylinder..

Rigidly securedl to said piston stem 1s a knurled head 21 which is utilized to rotate the stem to adjustably move the piston toward or from the gas duct 16 for the purpose of increasing or diminishing the effective capacity of the cylinder bore.

22 represents a plunger operable within the s cylinder and is of a len h approxlmate y equal to the distance tween the outlet and inlet openings 23 and 24 of a bypass connection 25 which is utilized toreceiver B, is a rod 27 which is surrounded.

by a helical spring 28 interposed between the plug 151 and a collar 272 provided on the rod. This sprin is operated through the energy derived rom the gas pressure and serves with the latter to actuate the ,hereinafter described gun mechanisms.

30 represents the breech-bolt having laterally arranged flanges extending. into. iideways 31 (Fig. 7) provided in the rame or receiver B and is rovided adjacent to its sides with depen ing rack teeth 32 which are engaged 'by the teeth of sectorgears 33, said gears being pivotally connected by a bolt`34 to supporting posts 35 of the receiver. These sector gears are connected from studs 36 thereon by means of operating bars 37, one on each sidefwith a cross-head 38 secured tothe rod 27 so that when the latter is urged rearwardly or forwardly, the sector gears are influenced to retract or advance the breech-bolt 30. The connections between the sector gears and said operating bars are, however, arranged to afford relative lost motion which is obtained by the provision of an elongated slot, such as 372, Fig. 13, into which extends the respective stud 36.

The hammer 39 is pivotally connected by a pin 40 to 'post 41 and is moved into cocked position by the breech bolt in opposition to the main spring 42 engaging by its bifurcated end the horns 43 provided on the hammer, as shown. Said spring is substantially of the form of a letter C, being secured to the receiver by'means of an attachment 44.

This spring is also arranged to be used to regulate the trigger 45 by having its end 46 bear downwardly upon a tongue 47 of the trigger whereby the arm 451-of the latter is' yieldingly held in the hammer notch 48.

To fire the gun singly, the trigger is used as in ordinar firearms to release the hammer and ena le the main spring to assert upon occasion, is encountered by a .bill 53 y 55 to a pair of arms 56 of levers 5 6-561 which are pivotally connected by a pin 57 to the elements of a slotted post 58.

Said lever arms are connected at their lower ends by pivotal studs 59 extending into slots, such as 371, provided in the respective operating bars 37 so that when the latter are pulled forwardly, the lever arms 56 act through the medium of the fingers 54 and 49, to cause the trigger 'to release the hammer through the agency of the bill 53 of one linger engaging the lug 52 of the other one during the last portion of the for- -ward movements of the operating bars and the breech-bolt.

Tov render the above-described automatic mechanism inoperable'when it is desired to use the gun for single firing, the finger 54 Yis tilted upwardly into approximately the position whereat it is indicated by broken lines 54x in Fig. 3. This linger' is thereby prevented from engaging the other finger 49; for which purpose I provide within a hollow `post 60 a vertically movable bar 61 having a slot 62' (Fig. 7) through which extends the finger 54 and, as shown, is connected to the bar for vertical movements ,formed at the rear end-of a pulling linger" 54 whose forward end is connected by a pin by means of a pin 63 extending through a slot 64 of the finger.

The 'bar 61 is provided with a screwthreaded stem 611 engaging in a nut 65 having a peripheral fian'ge 66 disposed between the underside of the receiver and a recessed plate 67 secured to the latter.

For locking the breech-bolt, I provide upon the latter spring latches 68 each having a tooth element 681 extending downwardly through an aperture 69 provided in the breech bolt to engage in a notch 70 provided in the arcuate extremity of the respective lever arm 561 when the breech-bolt arrives in the -position (Fig. 2) which it occupies when the gun is in tiring condition.

The action of the locking mechanism may be explained. as follows--Assuming the various parts to be in the positions in which they are illustrated in Fig. 2, when the operating bars 37 are driven rearwardly by the power of the powder gas, the levers 56---561 are thereby first actuated toward the teeth 681 of latch 68 upwardly, whereupon the =breech-bolt is released, the continued movement of the operating bars, the studs 36 are engaged thereby resulting in the sector gears 33 being influenced to effect the retract1on of the breech-bolt.

During the return, or forward, movement of the breech-bolt, the referred-to latch teeth 681 encounter the curved extremities 7 of the levers to thereby be influenced to elevate the locking tooth until the notches 70 are presented at or about the time the breechbolt is at the end of its travel when the resiliency of the latches will effect their engagement in the lever notches to accordingly lock the breech-bolt.

75 represents a suitable magazine detachably secured, as by .intertting devices 76, 77, to the side of the receiver B and is provided with means, not shown, to supply,

xed charges of 'ammunition through a feed opening 78 into the receiver and upon a lifter 79 whereby the charges are successively elevated'into the path of the breechbolt to be driven forwardly thereby into the barrel. l The lifter 79 is in the nature of a block having a groove 80 in its upper surface in which a charge is seated and is provided in its underside with a longitudinal recess 81 between spaced wingelements 82 to receive the forward arm 83 of a lever which is fulcrumed by a pin 84 to the post 58, and having its other arm 85 directed rearwardly and disposed so that it will be held by the weight of the lifter 79 in contact with an inclined bearing surface 301 in the underside of the breech-bolt 30 when the latter is in its forward position, as shown in Fig. 2.

When the breech-bolt retracts, the lever arm 83 continues to contact with, while being slightly depressed by, the block surface 301 until a roller 99 carried by the breechbolt engages such arm to further depress the same, resulting in the raising of the lifter into position (Fig. 3), whereat the elevated charge may be introducedsinto the barrel by the breech-bolt'in its succeeding forward" stroke. l

The lever-arm 83 is advantageously connected with said lifter by the provision of a coupling member 87 having a slot to receive such lever-arm and being Journaled for oscillatory' movements in the block wing elestops Such as 88which limit the upward travel of the lifter.

The charges areintroduced into the barrel-bore by the breech-bolt in its forward'` movements.4 The shells are ejected from-theY gun through an opening 9() in the side of the receiverY opposite the aforesaid feed-opening by means of devices indicated by 91 and 92 attached to opposite sides of the breechbolt and which may be of any ordinary or suitable type.

The gun is initially rendered operative ,by means of a crank 94 secured to a squared end of the bolt 34 as by means of a screw 341.

The construction and operation of the various mechanisms employed in my gun will, it is thought, be understood from the foregoing description.

l. In a gas-operated gun, a pressure cylinder communicatively connected with the gun barrel bore, a plunger operable withiny said cylinder, a by-pass havlng openings into the cylinder, said openings being spaced to accommodate the plunger therebetween, and an exhaust port provlded in the cylinder intermediate said by-pass openings.

2. In a gas-operated gun, a pressure cylinder communicatively connected with the gun barrel bore, a plunger operable within leasably securing the breech-bolt in .its forward position, and a reciprocating operating bar for disengaging said locking devices from the breech-bolt and subsequently influencing said sector gear to retract the breech-bolt.

llO

4. In a gas-operated gun, a breech-bolt *Y provided with rack teeth, a sector-gear engaging therewith, locking devices for releasably securing the breech-bolt in-its forward position, and a reciprocating operating bar connected to said devices and to said sector gear to primarily render said locking devices inoperative and subsequently afford motion to said sector gear to retract the breech-bolt.

5. In a gun, .the combination of a reciprocating breech-bolt, a hammer, a main spring therefor, a spring-regulated' trigger engageable with said hammer to releasably retain the latter in cocked relation, an operating bar operatively connected with said breech-bolt, means to reciprocate said bar to cock the hammer through the instrumentality of the breech-bolt during the rearward'movement of the bar and enable the trigger to engage the hammer, releasable means for coupling the trigger with said bar whereby the trigger is disengaged from the hammer by the forward movement of the bar, and meanswhereby said releasable means are rendered inoperable to release the trigger with respect to the hammer.

6. In a gas-operated gun, a`breech-bolt having a resilient latch depending therefrom, an operating bar, operative connections between the barand the breech-bolt,

said bar being reciprocated through the power derived from the pressure of powder gas, locking devices for engaging the latch.

of said breech-bolt, said locking devices consisting of a lever provided with an arm having a curved extremity and a latch-receiving notch extending therein, operative connections between said lever and said operating bar .whereby the lever is affected-to present the notch thereof in position to receive .said latch' after the breech-bolt has reachedwith the breech-bolt, a reciprocating operatingbar for actuating said breech-bolt, a

hammer adapted to 'be cocked by the breechthe last-named finger to render it operablel or inoperable with respect to the first-named finger whereby the trigger may be selectively actuated either automatically or manually to release:- the hammer.

9. In, a machine gun, the combination with the breech-bolt, a reciprocating operating bar for actuating said breech-bolt, a hammer adapted to be cocked by the breechbolt in its rearward travel, a trigger engageable with the hammer, means operatively connectin said operating bar with the trigger for disengaging-the trigger from the hammer during the forward movements of the operatin bar, and means4 regulated from outside o the gun receiver whereby said means are rendered temporarily inoperable.

10. In a gun, a breech-bolt provided with rack-teeth, sector gears engaging therewith, breech-bolt locking devices including vibratory levers, reciprocating bars con` necting the levers of said locking devices with the sectorv gears, and powder-gas operated means and manually operable means adapted to be used selectively forno erating the breech-bolt and the locking devlces.

Signed at Seattle, Washington, this 14th day of May, 1917.

wILLiAM R. CLARK. 

